
When your furnace reaches the end of its life, replacing it at the right time saves you money and keeps your home safe. We install high-efficiency furnaces from trusted brands and make sure the system is sized correctly for your home. A bad install causes problems for years — we do it right the first time. Whether you are upgrading an older unit or replacing one that has failed, we handle the whole job.

A furnace that stops working in the middle of a Massachusetts winter is not something you can wait on. We diagnose the problem fast and give you a straight answer on what it will take to fix it. Most repairs are handled the same day. We work on all makes and models, so you do not need to worry about whether we can service yours.

Summers in central Massachusetts get humid and hot, and a properly installed AC system makes a real difference. We size the equipment to your home so it cools efficiently without running up your electric bill. If your old system is outdated or undersized, we walk you through your options before any work begins. The goal is a system that performs well for years, not just the first season.

When your AC stops cooling, we get to the root of the problem instead of guessing. Low refrigerant, failed capacitors, frozen coils — we have seen it all and know how to fix it. You get a clear explanation of what is wrong and what the repair will cost before we start. We do not recommend replacing a system unless it genuinely needs it.

Heat pumps are one of the most efficient ways to heat and cool a home, and we install and service them regularly. They work year-round, which means the installation has to be done correctly for both heating and cooling seasons. If your existing heat pump is not performing the way it should, we diagnose and repair it quickly. We work on both ducted and ductless heat pump systems.

Boilers are common in older New England homes and require a technician who actually knows them well. We install new boiler systems and repair existing ones, from simple fixes to full replacements. Whether you have a gas, oil, or propane boiler, we service it. Consistent heat through your radiators or baseboard starts with a boiler that is running the way it should.

Mini-splits are a great solution for additions, older homes without ductwork, or rooms that never seem to get comfortable. We install single-zone and multi-zone systems and handle the full job from start to finish. If you already have a mini-split that is underperforming or making noise, we service those too. It is one of the most flexible and efficient options available for home comfort.

Most HVAC problems do not come out of nowhere — they build up over time when systems are not maintained. A seasonal tune-up catches small issues before they turn into expensive repairs. We clean, inspect, and test your equipment so it runs efficiently through peak heating and cooling season. Staying on top of maintenance also extends the life of your system.

We are available 24 hours a day, 7 days a week, including holidays. When your heat goes out at 2 AM in January or your AC fails during a heat wave, you need someone who actually answers. We respond fast and arrive prepared to get your system running again. Emergency calls are handled with the same care and quality as any scheduled appointment.

The air inside your home affects how comfortable and healthy your space feels every day. Poor ventilation, excess humidity, and airborne particles are all problems we can address. We assess your current setup and recommend solutions that fit your home and budget. Better air quality is one of those things people notice immediately after we improve it.

Your thermostat controls how your entire HVAC system behaves, and an outdated one wastes energy and causes inconsistent temperatures. We install programmable and smart thermostats that give you better control and lower utility bills. If you have already purchased a smart thermostat and are not sure how to set it up properly with your system, we handle that too. A correctly configured thermostat makes a noticeable difference in comfort and efficiency.

Leaky or dirty ductwork forces your HVAC system to work harder and delivers uneven temperatures throughout your home. We clean ducts to remove built-up dust, debris, and allergens, and we seal leaks that are causing you to lose conditioned air. This is especially common in older homes across central Massachusetts where ductwork has not been touched in years. The results show up on your energy bills and in how evenly your home heats and cools.
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Shawn and Julia Shelly built this business in Winchendon because this is where they live and work. Serving neighbors in Worcester County, Franklin County, and beyond means something different when you are part of the same community. Every call gets handled like it matters — because to a local family business, it does. This is not a franchise operation or a large company sending out whoever is available.
Most HVAC problems do not happen during business hours. That is why Shelly Heating and Cooling operates 24 hours a day, every single day of the year. When something breaks down in the middle of the night or over a holiday weekend, you reach a real person who can help. Being available all the time is not just a selling point — it is the standard we hold ourselves to for every customer we serve.

Shawn and Julia Shelly run this business themselves. That means every job reflects directly on their reputation in the community. You are not dealing with a rotating cast of subcontractors or a call center in another state. When you call Shelly Heating and Cooling, you are reaching the people who actually stand behind the work.
There is no after-hours voicemail that gets checked in the morning. When you call at midnight with a heating emergency, someone answers. We built the business around being available when it matters most — not just during the hours that are convenient for us. Central Massachusetts winters do not work on a 9-to-5 schedule, and neither do we.
You get a clear answer on what the repair or installation will cost before any work starts. No vague estimates, no surprise charges after the job is done. Customers in Winchendon and the surrounding towns trust us because we say what we mean and do what we say. That kind of straightforward approach is rare, and we take it seriously.
We have worked on homes and systems throughout Worcester County, Franklin County, and southern New Hampshire. We know the types of homes in this region, the age of the equipment commonly found here, and the weather demands these systems face. That local experience means faster diagnosis and repairs that actually hold up long-term.
Yes — we are available 24 hours a day, 7 days a week, including weekends and holidays. If your furnace stops working or your AC fails, you can call (978) 868-3403 at any hour and reach us directly. We serve Winchendon and surrounding towns in Worcester County and Franklin County. Emergency calls are treated with the same care and quality as any scheduled appointment.
We serve a wide area across central Massachusetts and southern New Hampshire. This includes Gardner, Athol, Fitchburg, Leominster, Templeton, Ashburnham, Westminster, and many towns throughout Worcester County and Franklin County. We also serve communities in Middlesex County and southern NH towns like Jaffrey, Rindge, and Peterborough. If you are not sure whether we cover your area, just call and we will let you know right away.
A furnace that needs frequent repairs, produces uneven heat, or is over 15–20 years old is usually a strong candidate for replacement. If it is still relatively new and the repair cost is reasonable, fixing it almost always makes more sense. We give you an honest assessment — we are not going to push a replacement when a repair will do the job. You will get a clear breakdown of both options so you can make the right call for your home and budget.
Yes — we service and install gas, oil, and propane heating systems, including furnaces and boilers. Older homes throughout central Massachusetts often have oil boilers or baseboard heating systems, and we have extensive experience working on them. We also handle conversions when homeowners are looking to switch fuel sources. Whatever type of heating system you have, we can work on it.
Most HVAC systems should be serviced at least once a year, with twice a year being ideal — once before heating season and once before cooling season. Regular tune-ups keep the system running efficiently, reduce energy costs, and catch small issues before they become expensive repairs. Skipping maintenance is one of the most common reasons systems fail prematurely in New England homes. A quick seasonal visit is far less costly than an emergency call in January.
Shelly Heating and Cooling is a locally owned and operated business based in Winchendon, MA — not a franchise or a large regional chain. Shawn and Julia Shelly own and run the business themselves. Being local means you are working with people who live and work in the same community you do. That makes a real difference in how jobs get handled and how much they care about the outcome.
Absolutely — that is actually one of the main reasons homeowners in this area choose mini-splits. Older homes in Winchendon, Athol, and Gardner often lack central ductwork, and a ductless system is one of the cleanest solutions available. We install single-zone and multi-zone systems depending on what your home needs. The installation is typically completed in one day and gives you both heating and cooling in one system.
Call us directly at (978) 868-3403 — we answer 24 hours a day, including overnight and on weekends. Do not wait until morning if the temperature in your home is dropping, especially if you have children or elderly family members in the house. We will diagnose the problem and work to get your heat restored as quickly as possible. In the meantime, keep interior doors closed to retain warmth in the rooms you are using.